For us here in the in the bright and beautiful future, some possibilities:
1. Try restarting Apache (or whatever you're running).
2. Consider browser caching and do things like deleting cookies, history, etc. Consider using a browser plugin such as CookieMonster (so you can selectively delete cookies for only the phpmyadmin site and not ALL sites and preserve the cookies that make life easier for you (such as the one that remembers your login username].
I was able to get this to work on my setup (Win 10/Firefox 48.0) without doing any of the above, but who knows.

BTW: I wandered into this forum from the cold dark Internet following a Google search on "blowfish secret" so I don't know what AMPPS is and thus my suggestions might be ridiculous and inane. :P